Pakistan has shifted 100,000 troops from its eastern border with India to its western border with Afghanistan to meet domestic terror threats, the Pentagon said on Thursday.

"More than 100,000 PAKMIL (Pakistan military) troops were moved from the eastern border with India. This unprecedented deployment and thinning of the lines against India indicates that Islamabad has acknowledged its domestic insurgent threat," the US Department of Defense said in a report to the US Congress.

The "Report on Progress toward Security and Stability in Afghanistan" said that over 130,000 Pakistani troops were participating in the ongoing campaign against the Taliban in Pakistan's tribal region.

"These operations represent the largest deployment of PAKMIL forces on the western border of Pakistan in the nation's history, with over 130,000 PAKMIL deployed to the FATA (Federally Administered Tribal Areas) and Northwest Frontier Province (NWFP)," it said.

The report named terrorist organisations that "threaten security" in India and other countries.

"The insurgency is comprised of multiple groups pursuing various short and longer-term goals. They are part of a broader syndicate of extremist groups including Al Qaeda, Pakistani Taliban and Lashkar-e Tayyiba (LeT) that threatens security in Afghanistan, Pakistan, India, and elsewhere," it said.

"The three major groups include the Quetta Shura Taliban, Hezb-e Islami Gulbuddin (HIG), and the Haqqani Network (HQN). The common goals of these groups are to expel foreign forces from Afghanistan and to undermine the central government," the report added.

It said Pakistan military had suffered terrorist attacks because of its operation against militants.

"Pakistan has suffered attacks from terrorists in response to its successful operations. While these attacks do not appear to have shaken Pakistan's commitment, they do demonstrate, for the time being, insurgent ability to continue attacks despite reported successful PAKMIL operations," the report said.